Future progress in the treatment of childhood cancer is dependent upon the development of more efficacious and less toxic novel therapeutic agents. This proposal will detail the infrastructure and research objectives of the Children's Oncology Group (COG) Phasel/Pilot Consortium that has been developed to meet the new challenges of developing conventional and molecularly targeted drugs for pediatric cancers. The mission of the COG Phasel/Pilot Consortium is to identify and develop effective new agents for children and adolescents with cancer, through scientifically rational and efficient clinical and laboratory research. The new Consortium is comprised of COG institutions who, based on the results of an objective, peer-reviewed process, were found to have the best capability of accruing patients to phase l studies; the necessary infrastructure to carry out phase l and pilot studies including correlative studies; and the most qualified and experienced investigators in pediatric cancer drug development. The Consortium has been structured to have a highly efficient and productive process for the development and implementation of pediatric phase l and pilot studies. The Operations Center and Statistics and Data Center are closely integrated to provide efficient support of the administrative, regulatory compliance, financial management, study coordination, data acquisition, statistical science, quality assurance, and performance monitoring activities of the Consortium. The Consortium has indepth experience in developing a broad spectrum of new agents for children with cancer, including cytotoxic drugs, biologic agents, modulating agents, and signal transduction inhibitors. An infrastructure for performing pharmacokinetic, pharmacogenetic and other correlative biologic studies, integral components of the Consortium's scientific mission, utilizes the expertise of the most highly qualified investigators and laboratories within the COG. With an increasing number of investigational agents available for study, the most important consideration in the conduct of pediatric phase 1 trials will be selection of appropriate agents for evaluation. The Consortium's prioritization process utilizes data emerging from pre-clinical models in developing recommendations for prioritization of new agents to study within the Consortium. A Pre-Clinical Advisory Group of leading laboratory and clinical scientists has been formed to advise the Consortium during the prioritization process. The Consortium's infrastructure allows for flexibility in the development, design and performance of phase l and pilot studies, and is able to respond to advances in cancer therapy with the timely implementation of a scientifically sound clinical trials.